In the early 1970s, the Clean Water Act (Public Law 92-500) helped focus attention on entrainment and death to larval Great Lakes fishes by thermal-electric generating stations using lake water for cooling.  Thermal discharges were addressed in section 316 and paragraph ‘a’ asked dischargers that their thermal waste “assured the protection and propagation of a balanced, indigenous population of shellfish, fish and wildlife in and on the body of water”.  Section 316 (b) of this law required examination of cooling water intake structures to determine if best available technology was being incorporated to minimize impacts. Few taxonomic tools were available to assist scientists in identification of newly-hatched fishes and in 1976 a “Great Lakes Fish Egg and Larvae Identification” workshop was held in Ann Arbor, Michigan sponsored by the National Power Plant Team to begin to address these needs.

The University of Michigan Great Lakes Research Division fish laboratory, a leader in power plant study and fish identification, headed by Dr. David Jude, had a contract in the late 1970s with Consumers Power Company for 316 (a) and (b) demonstrations and a group of dedicated individuals devoted much spare time to construction of what has been termed ‘The Atlas’.

The individuals responsible for completing this 744 page work included: Nancy Auer, Dr. David Jude, Lee A. Fuiman, George R. Heufelder, and Heang T. Tin. Some funding and publication was provided by The Great Lakes Fishery Commission, Ann Arbor, MI.

See also "Identification of Larval Fishes of the Great Lakes with Emphasis on the Lake Michigan Drainage," N. Auer editor, with forward prepared by Carlos Fetterolf, Jr., Executive Secretary, Great Lakes Fishery Commission, 1982.

The above 1982 publication, which is now being adapted for an interactive key to the larval fishes of the Great Lakes, was a summary of a broad search for literature to approximately 1981. Techniques and procedures for larva identification varied and myomere counts used in species descriptions varied due to techniques used by authors.  Preanal myomere counts reported by Fish 1932, Nelson 1977, Norden 1961 and in some older works are the number of entire myomeres from the nape to the anus.  The counts reported in Fish 1932 have been omitted since her work does not correspond with more recent data.  Other more recent work describe preanal myomeres as those from the nape to an imaginary vertical line drawn at the posterior edge of the anus, including any bisected by that line Buynak and Mohr 1978-1980, Cooper 1978, Fuiman and Loos 1977, Hardy 1978, Lippson and Moran 1974, Mansueti 1964, Mansueti and Hardy 1967 and Seifert 1969. 

Current Online Keys:

In 2014, under a project funded by the Electric Power Research Institute, LimnoTech (Ann Arbor, Michigan) collaborated with Dr. Nancy Auer to initiate the development of an open-access, web-based version of the original taxonomic key. LimnoTech worked closely with Dr. Auer to create a single, updated taxonomic resource for larvae and eggs for fishes of the Great Lakes region. The newly converted key included a total of 153 species from 25 families. The timing of the converted key was intended to assist facilities and taxonomists with the processing of cooling water entrainment characterization samples conducted to comply with the EPA's final 316(b) rule (USEPA, October 2015). 

The original freshwater key has been expanded to include several additional basin areas throughout the U.S. including the Colorado River basin, the Tennesee and Mississippi Rivers. Additional keys for Atlantic and Pacific regions have now also been added (see our reference shelf for details on references used to build the keys.